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The inverse square law of lighting

Many considerations come into play with group portraits: posing, wardrobe and the right camera angle among them. But lighting adds an additional layer of complexity and potential confusion. This is because lighting group portraits is technically counterintuitive, or at least it was for me. In this month’s column, I’ll demystify one of the governing principles of lighting, known as the “inverse square law.”

THE BIG TAKEAWAY

A quick Google search brings up this definition of the inverse square law: “any physical law stating that some physical quantity or strength is inversely proportional to the square of the distance from the source of that physical quantity.”

You can skip the following paragraph if math scares you. But if you want to understand the basics of this law, read on.

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